Agitator



May 22, 1956 L. G. HILKEMEIER AGITATOR Filed Sept. 21, 1953 FIG.

LOUIS G. HILKEMEIER IN VEN TOR.

United States P tent '0 2,746,734 AGITATOR Louis G. Hilkemeier, Plainfield, N. J assignor to Worthington Corporation, Harrison, N. 1., a corporation of Delaware Application September 21, 1953, Serial No. 381,405 2 Claimsi- Cl. 259-161) This invention relates generally to transit type concrete mixers and more particularly to an improved transit mixer adapted to haul a rated load as an agitator without using a closure means for the discharge opening thereof.

Transit type concrete mixers now in commercial use generally include an inclined type mixing drum having either a single end opening or an end opening and a side hatch. When such transit type mixers are adapted to haul a rated load from a central mixing plant to the job they use either a combined closure and charging hopper or a separate closure cover for the end opening. When so used they are termed agitators.

It has been found that the closure means for the end opening may beentirely eliminated by adapting the last few feet of the mixing and discharging blades inside the drum to act as a closed vein structure to prevent discharge of the concrete from the drum.

The present invention covers a means for forming this closed vein structure in the form of a truncated coneshaped element closed at at least one end which is disposed in the mixing drum just inwardly of theend opening on the inner aspects of the mixing and discharging blades.

The absence of a closure means for the end opening eliminates the initial cost of the closure means for the end opening and its operating mechanism and also the maintenance repairs normally necessary thereon.

Accordingly, it is an object of the present invention to provide an improved agitator adapted to haul a rated load without requiring a closure means for the end opening of the mixing drum thereof.

With this and other objects in view, as may appear from the accompanying specification, the invention consists of various features of construction and combination of parts, which will be first described in connection with the accompanying drawings, showing an agitator of a preferred form embodying the invention, and the features forming the invention will be specifically pointed out in the claims.

In the drawings:

Figure 1 is a diagrammatic sketch of an agitator.

Figure 2 shows the mixing drum partly in section showing the invention. a

Figure 3 is a view from the end opening showing the invention.

Figure 4 shows the truncated cone-shaped element itself.

Referring more particularly to the drawings, Figure 1 shows diagrammatically an improved agitator unit gen erally designated 1. The agitator 1 includes a truck frame 2 and a rotatable mixer 3. The rotatable mixer is the inclined type having the front or closed end lowermost and is pivotally and rotatably mounted in the truck frame 2 in the manner well known in the art. The mixice the mixing drum is not more fully described as they are also well known in the art and are considered only in relation to the general combination to which the present invention is applicable. Thus, when the prime mover is started and is engaged the transmission will rotate the mixing drum in either clockwise or counterclockwise direction.

Figure 2 shows the mixing drum 3 having a substantially hollow cone or top-shape with an end opening 7 and a side hatch 8. The side hatch 8 is provided with a removable cover 9 and is opened by rotating the handle 10 when the hatch is in the top center position as shown in Figure l. The mixing drum is filled through the hatch 8 and after the concrete is mixed is discharged by the mixing and discharging blades 11 through the end opening 7 as hereinafter described. It will be understood that while a hatch is shown that if the mixing drum had only a single end opening that it would be possible to charge and discharge the mixer through this single end opening.

Aflixed to the inner wall of the mixing drum by suitable means are a plurality of mixing and discharging blades 11 which extend radially inward from the inner wall of the mixing drum and are spirally disposed along the inner wall commencing at the end opening 7 and extending axially rearward, all of which is clearly shown in Figures 1, 2 and 3 of the drawings.

When the mixing drum is rotated in one direction the blades 11 act to mix the ingredients in the mixing drum, and when rotated in the other direction the helix or spiral construction of the blades acts to move the concrete forward along the blades to the end opening 7, from which it is discharged.

Just inwardly of the open end of the drum is a closed ended truncated cone element 12 shown in Figure 4 of the drawings which has its closed end disposed closest to the end opening 7.

The inner aspects of the radially extending portion of the blades or vanes 11 adjacent to the end opening 7 are connected to the outer surface of the truncated cone element 12 so that the truncated cone element is also held in spaced relation to the inner walls of the mixing drum and will have the closed end positioned as above described, all of which is clearly shown in Figure 2 of the drawings.

It is the positioning of this truncated cone element 12 in association with the blades 11 and the inner wall of the mixing drum which form in the last few feet adjacent ing drum 3 has a conventional ring gear 4 shown on the the end opening the closed veins or passages 13.

When the drum is rotated in the mixing direction the mixture in the drum cannot float past the closed passages 13, hence all spillage is avoided. Conversely, when the drum is rotated in the discharging direction the passages are open to receive the mixed concrete by the helix or screwing action of the blades 11.

It will be understood that the invention is not to be limited to the specific construction or arrangement of parts shown, but that they may be widely modified Within the invention defined by the claims.

What is claimed is:

1. An agitator for transferring concrete comprising, a truck frame, and inclined rotatable mixing drum mounted in said frame having a side hatch for charging and an end opening for discharging said drum, means for rotating said mixing drum, a plurality of spiral blades disposed on the inner wall of said mixing drum for discharging mixed concrete from said mixing drum when said drum is rotated for discharging, a cylindrical element in said drum adjacent said end opening and held in spaced relation from said walls to form closed veins with said blades, said cylindrical element closed at its outer end to prevent mixed concrete from escaping through said end opening.

2. In an agitator comprising, a truck frame, an infeet of said blades to prevent spillage, and said truncated clined rotatable mixing drum mounted in said frame cone closed at the end thereof adjacent said end opening. having a side hatch for charging and an end opening for discharging said drum, means for rotating said mixing References Cited illth file of this Patent drum, a plurality of spiral blades disposed on the inner 5 UNITED STATES PATENTS wall of said mixing drum extending from the end opening rearwardly about the axial line of said drum and pro- $333 I :5 'fi ectmg radially inward, a truncated cone element, said 2394.453 Huszar Feb. 5, 1946 truncated cone having its exterior wall connected to the inner aspects of said blades and disposed just inwardly of 10 2678197 Oury May 1954 the end opening to form closed veins with the last few 

